The Surface Properties of PAVAc Prepared by Dispersion Polymerization in ScCO2

Dispersion copolymerization of acrylonitrile-vinyl acetate (AN-VAc) has been successfully performed in supercritical carbon dioxide (ScCO2) with a series of lipophilic/CO2-philic diblock copolymers, such as poly (styrener-acrylonitrile)-b-poly (1, 1, 2, 2-tetrahydroperfluorooctyl methacrylate) (PSAN-b-PFOMA), as steric stabilizers. The structure and the particle morphology of the product were characterised by FT-IR and SEM. In addition, the effects of the stabilizer on the surface properties of the products were investigated in detail. Results indicate that the surface free energy of the poly (AN-r-VAc) (PAVAc) film decreases dramatically because of the existence of the stabilizer. And, when the initial concentration of the monomer was 10% (the mass (g) of monomer to the volume (mL) of ScCO2) the optimal concentration of the stabilizer is about 5% (w/w% to monomers).